1. Field of the Invention
The present invention relates generally to envelope inserters and more particularly to an improved bridge assembly for a reciprocating ram type envelope inserter.
2. Brief Description of the Prior Art
Inserters have played a significant role among the labor saving devices available to businesses which were engaged in the daily mailing of large numbers of pieces. Among the advantages of inserter usage has been the reduction in personnel required to produce large quantities of outgoing mail. Further, mail room personnel have been relieved of the monotonous task of individually stuffing a seemingly insurmountable number of envelopes. Inserters have been particularly well adapted for use in the mailing of form letters and the like and have been employed for the insertion of personalized documents, e.g. computer generated letters, checks, tab cards, etc., into window envelopes.
In U.S. Pat. No. 2,914,895 issued Dec. 1, 1959 to Samuel W. Martin, and assigned to the assignee of the present invention, an envelope inserter having a reciprocating ram blade with an enclosure pusher secured to the blade undersurface was described. The ram blade was mounted for reciprocal movement along a horizontal plane from a home position, in front of an enclosure pick-up station, to an envelope station. The pusher engaged the enclosure beneath the ram blade and drive it into the envelope.
Such operating mode was typical among the Pitney Bowes Series 3300 inserters. Enclosures were fed from an enclosure feeder to the pick-up station by a pair of transport belts. Skis mounted to the underside of a cover or bridge plate in registry with transport belts urged each enclosure into driving engagement with its respective belt. The bridge or cover plate carried an enclosure pick-up station gate adjacent its forward end.
In the Pitney Bowes Model 3320 Insertermate inserter, the enclosure gate was positioned beneath, i.e. tucked under, an envelope flapper which was part of an envelope feeding assembly. Additionally, a rigid bridge bracket was secured to the inserter frame and overlied the bridge plate. The bridge bracket provided a rigid mount for a double detector switch. Adjustment of the switch was possible only when the operator leaned over the top of the machine and grasped an adjustment knob which projected from the top of the bracket. Because the adjustment knob and other projections extended from the top of the bracket, the bracket did not present an obstruction free flat surface for tamping enclosures into orderly stacks prior to loading and a table or other work surface was often necessary.
In addition, the bracket was not user removable in the event one or more enclosures become jammed along the pathway beneath the bridge. In the event an enclosure jam occured at the pick-up station, the enclosure gate was movable to access the pick-up station, however it was first necessary to move the envelope flapper. Difficulties encountered in removing jams in the transport pathway and at the pick-up station often rendered an inserter inoperative and a service call was required. Furthermore, accessing the pick-up station or the ram mechanism for adjustments required the envelope flapper to be rotated to a non-operative position clear of the enclosure gate door. Additionally, mail room personnel often neglected to restore the envelope flapper to operative position which resulted in the seemingly inexplicable failure of the inserter to operate.